Diabetes mellitus, commonly called diabetes, refers to a disease process derived from multiple causative factors and characterized by elevated levels of plasma glucose, referred to as hyperglycemia. There are two major forms of diabetes: Type 1 diabetes (also referred to as insulin-dependent diabetes or IDDM) and Type 2 diabetes (also referred to as noninsulin dependent diabetes or NIDDM).
Type 1 diabetes is the result of an absolute deficiency of insulin, the hormone that regulates glucose utilization. This insulin deficiency is usually characterized by β cell destruction in the pancreas, which usually leads to absolute insulin deficiency. Type 1 diabetes has two forms: Immune-Mediated Diabetes Mellitus, which results from a cellular mediated autoimmune destruction of the β cells of the pancreas; and Idiopathic Diabetes Mellitus, which refers to forms of the disease that have no known etiologies.
Type 2 diabetes is a disease characterized by insulin resistance accompanied by relative, rather than absolute, insulin deficiency. Type 2 diabetes can range from predominant insulin resistance with relative insulin deficiency to predominant insulin deficiency with some insulin resistance. Insulin resistance is the diminished ability of insulin to exert its biological action across a broad range of concentrations. In insulin resistant individuals, the body secretes abnormally high amounts of insulin to compensate for this defect. When inadequate amounts of insulin are present to compensate for insulin resistance and adequately control glucose, a state of impaired glucose tolerance develops. Insulin secretion may further decline over time.
Type 2 diabetes can be due to a resistance to insulin stimulating regulatory effects on glucose and lipid metabolism in the main insulin-sensitive tissues, such as muscle, liver and adipose tissue. This resistance to insulin responsiveness results in insufficient insulin activation of glucose uptake, oxidation and storage in muscle and inadequate insulin repression of lipolysis in adipose tissue and of glucose production and secretion in liver. In Type 2 diabetes, free fatty acid levels are often elevated in obese and some non-obese patients and lipid oxidation is increased.
Premature development of atherosclerosis and increased rate of cardiovascular and peripheral vascular diseases are characteristic features of patients with diabetes. As such there is a need in the art for improved compositions and treatments for diabetes and other conditions typically associated with patients having diabetes.